GSM stands for Global System for Mobile Communications. Just like computers, cellular telephone have developed over time. There were first generation cellular telephone in the 70's, there are 2nd generation cellular phone in the 80's and 90's, and now there are 3rd gen phones which are about to enter the Indian market. GSM is named a 2nd generation, or 2G communications technology. GSM or global system for mobile communication is a digital cellular system. It was originated in Finland Europe. however now it is globally. GSM (Global System for Mobile Communication) accounts for 80 % of total cellular telephone technologies market. There are over more 3 billion users of GSM (Global System for Mobile Communication) now. GSM technology got its status, when people used it to consult with their friends and relatives. The use of GSM (Global System for Mobile Communication) is possible due to the SIM (subscribers identity module) GSM (Global System for Mobile Communication) is easy to use, affordable and lets you carry your cell phone everywhere. GSM (Global System for Mobile Communication) is a 2G technology. There are many frequency ranges for GSM (Global System for Mobile Communication) however 2G is the most used frequency. GSM (Global System for Mobile Communication) offers restrained security. It allows for encryption between the end user and the service base station. The use of various forms of cryptographic modules is part of GSM technology. GSM makes use of two principles :. Time division Multiplexing. Therein multiplexing, the radio frequency say 890 Mhz is shared by different users in time. This means if user A, B, C and D all talk at the same time. You assign the 890 Mhz frequency to A for some time and allow him to talk, then you assign 890 band to B for sometime to speak, then to C, and finally to D, before return to A. So the process continues in a round robin fashion, as long as A, B, C, and D want to talk. This way many users talk at same time on the same frequency. This has to be done, because as we now frequency or Bandwidth is a scarce resource and is not available in plentiful, so it must be shared. Frequency Division Multiplexing. Therein multiplexing, users A, B, C and D, all use different frequency say 890, 900, 910, 920 for their respective communications. A very example of this is Radio broadcasting. Because all the radio operators like Rad FM, Go FM, Radio Mirchi want to operate in the same area, they use different frequencies for communication 91.0 FM, 93.5 FM, 94.6 FM, 108FM. So to listen to different communications, you have to tune in the receiver set to different frequencies. GSM uses a combination of TDMA and FDMA. This means that users A and B are not only sharing the channel in time but also frequency. This means that user A is on the channel 890Mhz for 2 seconds, then jumps to 900Mhz channel for the next to seconds, then jumps to 910Mhz for the next 2 seconds etcetera... Thus, each user is uses a different frequency at different time slots. This is called Frequency Hopping. Concisely we can say : 1. GSM stands for Global System for Mobile Communication and is an open, digital cellular technology used for transmitting mobile voice and data services. 2. The GSM emerged from the idea of cell-based mobile radio systems at Bell Laboratories in the early 1970s. 3. The GSM is the name of a standardization group established in 1982 to create a common European mobile telephone standard. 4. The GSM standard is the most widely accepted standard and is implemented globally. 5. The GSM is a circuit-switched system that divides each 200kHz channel into eight 25kHz time-slots. GSM operates in the 900MHz and 1.8 GHz bands in Europe and the 1.9 GHz and 850MHz bands in the US. 6. The GSM is owning a market share of more 70 percent of the world's digital cellular subscribers. 7. The GSM makes use of narrowband Time Division Multiple Access (TDMA) technique for transmitting signals. 8. The GSM was developed using digital technology. It has an ability to carry 64 kbps to 120 Mbps of data rates. 9. Presently GSM support more one billion mobile subscribers in more 210 countries throughout of the world. 10. The GSM provides basic to advanced voice and data services including Roaming service. Roaming is the ability to use your GSM telephone number in another GSM network.
http://mobileworldlimited.com/gsm-technology/
http://mobileworldlimited.com/6 views
Source: http://www.freepressreleases.com/gsm-technology/234105
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